<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="../css/bootstrap.min.css">
    <title>Bootstrap按钮式下拉菜单案例</title>
</head>

<body>
    <div class="container">
        <div class="btn-group dropup">
            <button type="button" class="btn btn-info btn-lg">分裂式下拉菜单</button>
            <button type="button" class="btn btn-info btn-lg dropdown-toggle" data-toggle="dropdown">
                <span class="caret"></span>
            </button>
            <ul class="dropdown-menu" role="menu">
                <li><a href="#">1</a></li>
                <li><a href="#">2</a></li>
                <li><a href="#">3</a></li>
                <li><a href="#">4</a></li>
            </ul>
        </div>


        <div class="btn-group">
            <button type="button" class="btn btn-info">分裂式下拉菜单</button>
            <button type="button" class="btn btn-info dropdown-toggle" data-toggle="dropdown">
                <span class="caret"></span>
            </button>
            <ul class="dropdown-menu" role="menu">
                <li><a href="#">1</a></li>
                <li><a href="#">2</a></li>
                <li><a href="#">3</a></li>
                <li><a href="#">4</a></li>
            </ul>
        </div>

        <div class="btn-group">
            <button type="button" class="btn btn-info btn-sm">分裂式下拉菜单</button>
            <button type="button" class="btn btn-info btn-sm dropdown-toggle" data-toggle="dropdown">
                <span class="caret"></span>
            </button>
            <ul class="dropdown-menu" role="menu">
                <li><a href="#">1</a></li>
                <li><a href="#">2</a></li>
                <li><a href="#">3</a></li>
                <li><a href="#">4</a></li>
            </ul>
        </div>

        <div class="btn-group">
            <button type="button" class="btn btn-info btn-xs">分裂式下拉菜单</button>
            <button type="button" class="btn btn-info btn-xs dropdown-toggle" data-toggle="dropdown">
                <span class="caret"></span>
            </button>
            <ul class="dropdown-menu" role="menu">
                <li><a href="#">1</a></li>
                <li><a href="#">2</a></li>
                <li><a href="#">3</a></li>
                <li><a href="#">4</a></li>
            </ul>
        </div>
    </div>
    <script src="../js/jquery-1.12.4.js"></script>
    <script src="../js/bootstrap.min.js"></script>
</body>

</html>